Cts_V

hey guys, i just got my kooks headers installed and it sounds awesome with the corsa..heres the dyno charts...



(gets larger if you clcik it)
on my way driving back home my car started hesitating and was making a very deep sound out the exhaust (almost like thunder) I brought it back to the shop and he said that one of my rear o2 sensors burned out. So he said that hes gonna order o2 sensor simulators.. any input on the o2 simulators?

THanks

2c5s

iTrader: (11)

You're very lean, you should get the car tuned. I'm not sure why the o2 would burn out ..... seems strange. Did they replace it or did they keep the car? Why did they end the second run earlier, looks about 6,300 rpm.

2k2blkss

Maybe I missed something here. But it looks like you gained 20 TQ but LOST 7 HP with the addition of the headers. You should really look into a tune. I'm still trying to figure the loss in power though even without a tune.

Cts_V

Yeah im planning on getting it tuned next week...the shops keeping the car untill they get the o2 simulators.

im not sure why i lost hp, hopefully the o2 simulators and the tune will help.

obZidian

iTrader: (2)

got agree with my friend there, your really lean. A new tune is a must if you dont want to run into any problems. Gota graph vs. rpm instead of speed?

On the simulators, have you modified your cats or have an off-road pipes (no rear o2's installed) Just trying to see why you want to run two simulators with you are still running both , pre and post sets? Tunnig preferences?

Personally, i wouldn't run that car hard at all until i get that afr down closer to 13.0 or below that by a bit. Also, your cars seems to be producing a bit under the norm...

becareful and get her tuned by some one else, see what they say...

good luck!!!

Cts_V

no sorry thats the only graph i have...i should have asked them for a graph with the rpm. I have high flo cats. As soon as i get the car back im making an appointment for a tune. Hopefully i wont have any problems before then.

obZidian

iTrader: (2)

Oh, no worries...

Well, im sure the sims might help you out, i remember when i was getting my dynatechs, with th eri hi-flow cats, i was looking into getting a set of sims but decided agains't it. I know run stock type o2's, deleted the rears through hptuners, and tune off one set (pre-o2 set)

Yeah, get here tuned right away, you dont want to hurt the motor. It could possible be that the extra heat generated by the lean condition, could have possibly burned out those o2's, if that is the wat happen. You said thunder right? Also, your motor was hesitiating... all these things can and should be fixed with the a new revised tune. If not, it maybe be something physical like a header not sealing or somthin of that nature. Hell, i once, after re-installing my heads, AGAIN, didn't plug in the main harness for the passenger plugs and i wasn't getting any spark... drove me nuts for a while!!

**** like that happens and its and easy fix. Just get here tuned adn wait until you get your foot in it.

Interesting, notice how your first run was richer than your second produced more power (hp) throughout the powerband. Well, if you get that afr under 13. a bit, you ,ight see an increase in over hp. you see, you are getting air in but not enough fuel is present to cause a solid hit. Add more fuel, but not to much under your PE tables, and you should see a bit more hp. These cars dyno somewhere in the 320+ range, give or take a few, however, you are making under that with headers and hi flow cats. Im not sure what your other mods are but that is a bit to low. It being another indication that your tune is off, that is all..

Good luck, see what your tuner says and if things dont go well, you can always find another tuner, some that has atleast tuned ls1's, and get her back inline. LAterZ!

Cts_V

is the cts-v like the other ls1's were the rear o2 sensors only make sure if the cats are there? if thats the case, then the rear o2 sensors isnt the problem for the car hesitating?

obZidian

iTrader: (2)

in a sense, not exactly. The rear o2's read the post a/f. Basically, the pcm relies on a pre o2 signal and a post o2 signal. It determines, by the values it reads, where to trim your fuel in order to maintain its pre-set a/f level. Also, they are there, since the pre's are located before the cats and the posts are after cats, it determines the amount of unburned gases and adjusts the motor parametes as well. So, yes and a bit more.

I dont believe the rear os'2 is the reason why your car is hesitating though it has been a known cause for hesitation. Try the sims out or just replace your o2's with a set of stock ones. If they are off, the motor could develop an incorrect fuel mixture, however, IMO, It would seem that your motor isn't getting enough fuel, its being starved. This creates an unwanted amount of heat. There might be a spoiled plug that isn't burning as well becuz of that excess heat. There are way too may factors that could result in a hesitation. Have you check your air intake plumbing. A bad seal with cause some hesitation or a stumble at idle. I would go one by, starting by the tune, then check your o2's and plugs, check for a loose plug wire or incorrectly installed spark harness. etc.

Have both o2 banks scanned and see if the fluctuate normally. bank 1 s1/ bank 2 s1 are your pre's, bank 1 s2/ bank 2 s2 are your posts. They should fluctuate very sprradically, if they seem stuck on a specific value like 5 or 8, you have a bad sensor. It should look like anything between 200-800 but going up and down rapidly. (that is a generalization, but, that is the jist of it!!)

good luck!!

2c5s

iTrader: (11)

Since you need to get the car tuned, why not just have your tuner turn the rear o2's off and save the money trying to replace them or buying o2 sims?BTW, the second run with the headers does NOT yield a 20 rwt increase, it's a spike.

Cts_V

i was thinking of that but they advised me not to drive the car till the sensors fixed. Im not sure how much it costs to tow but the place where im planning to get it tuned is about 1hr and half away. After the tune should the dyno number be where there supposed to be?

2c5s

iTrader: (11)

Where do you live and who is going to tune it. What year is your V?

Cts_V

its an 05 V. i live in florida, the name of the place thats going to tune it is revextreme

V-seriesTech

iTrader: (5)

I take it you live tampa, or nearby?

Cts_V

yes, petty close

V-seriesTech

iTrader: (5)

Cool deal,... i'm east.

obZidian

iTrader: (2)

Jeremy formato, if he is still there, will get here inline. I would tow it, personally, or, like i did, trailer it. A trailer isnt much really and since you going to the same state, it should be WAY less than what i dropped for my trailer. U-haul has them.

They are a good shop. Even if Jeremy isn't around, haven;t spoken to him in over two years now, i believe, you should be able to find someone there that can get you going straight.

good luck, let us know how it turns out huh!

Cts_V

well i called the shop today, they found the problem. One 02 extensions that came with the headers were bad and it fouled 4 spark plugs on the passenger side and burned out the rear o2...

obZidian

iTrader: (2)

well, that would do it. Question, do you know where they were gettn' your a/f readings from? Was it a dipstick looking thing (snifer) they inserted in your exhaust pipes or a 02 type of reading prob?

Maybe, that bad o2 was the cause of you leaning out so much? OR maybe not. Get it all replaced and on the dyno again. These motors like the 12.5 range for good solid, SAFE power levels. Some go up to 13.0 and some go higher. I would dont mind sacrificin a few extra ponies if it ensures the motor wont detonate, BAD!!

Cts_V

they used the thing that goes on the exhaust. How would the o2 extension foul out the spark plugs tho? do you think there was damage done since the 4 plugs were fouled? i only drove it mile or so...